Bound-edge plaster wall board



June 2, 1925.

C. W. UTZMAN BOUND EDGE PLASTER WALL BOARD V"Filed March 1,4, 1923` 2 sheets-sheet 1 1 N VE TOR, Clarence W. l/zman zii A TTORNE Y.

June 2, 1925.

C. W. UTZMAN BOUND EDGE PLASTER-WALL BOARD 2 Sheets-Sheet 24 Filed March 14. 1923 INVENTOR. 7a/*ence M /Izman A TTORNE Y.

Pagg Y Patent-ed June 2, 1925. i

vUNITED .sTATEs PATENT OFFICE.

CLARENCE w. UTZMAN, or CHICAGO, ILLINOIs, AssIGNoR To NI'I'ED srA'I'Fs GYPSUM COMPANY, or CHICAGO, ILLINOIS, A CORPORATION or ILLINOIS. 1

BOUND-EDGE PLAST-ER WALL BOARD.

To -aZZ 'whom t may cof/wem:

MAN, a citizen of the United States, residing at Chicago, in the county of C Ok and State of Illinois, have invented n w and useful Improvements in Bound-Edge Plaster Wall Board, of which the following is a specification. y

rIhis invention relates to building material-and more particularly to an improved bound edge plaster wallboard.

Plaster board in building construction has been used for a long time as a substitute for wooden laths or the like in the erection of walls and ceilings and,

having been nailed or otherwise secured to the studding or held in position, is given the usual coats of plaster .to surface the wall or ceiling. At first such plaster board was constructed in flat sheets having a plaster orl similar composition core with paper or fibrous material applied on each flat surface as a protective covering which also gave sufficient tensile strength to ing the handling necessary in transportation and erection. Plaster board of this character varied in thickness and dimensions usually7 36 long by 3 wide, as the and length were impracticable as the cover sheets would ypeel back and become torn in handling until the problem was solved by binding the longitudinal edges of. theboard as set forth in my Patent '1,034,746 lof August 6, 1912. After this discovery plaster panel orA wallboard came into vogue which could be `fabricated in 48 widths and of .a length to reach from ceiling to floor and in the development of plaster panel board. it -Was found that it could be made sufficiently smooth of surface and thick enough to Ob- `viate, the necessity of the heretofore usual coating of plaster so that the present plaster wallboard can' be applied directly to the studding and provides a finished surface ready for decorating.

This invention relates to`improvements in plaster wallboard constructed in accordance with my said Patent, 1,034,746, and possesses new and useful advantages thereover. It contemplates the production o f aplaster wallboard Of uniform thickness throughout Application filed March 14, 1923. Serial No. 624,931.

the core to maintain its conformation dur-` and in which the edges of the margins of Be it known that I, CLARENCE W. Ugrz the', cover sheet brought about the longitudinal edges of the composition core will not project above nor-cause 'the other cover sheet at its longitudinal margins to project above the main body of that side. This invention also contemplates 'they binding of; the edge in such a manner that while the thickness of the board. remains constant throughout, the longitudinal edges may be formed fiat and at any angle to the fiat main surfaces of the board desired, as well as providing means whereby the outer cover sheet may .be lbrought lsubstantially flush with the longitudinal edges and lie in the plane of the surface. on that side on which it terminates. 4 p

The .advantages of this particular construction of plaster Wallboard` will be pointed out as the different forms are described. With these and other vObjects in view, reference is had to the accompanying sheets of drawing, which illustrate the preferred forms of this invention with the understanding that minor detail changes may be made without departing `from the scopev thereof, and in' which like reference characters indicate like parts. l

trating a transverse edge in section, of one form of this invention.

Figure 2'is a view in transverse section, enlarged, of Figure 1-.

.Figure 3 is a view in transverse section illustrating an' application of this form of wallboard to a stud.

Figure A4 is a view in end elevation of one board as applied to a stud.-

`Figure 5 is a'view in perspective of a modified form of this invention.

Figure 6-is a view in transverse section, enlarged, of'Figure 5.`

Figure '7 is a top plan view, lwith parts'.

broken away, of the edge portion of Figure 5.

Figure 8 is a view in perspective of another form of this invention. i

Figure 9 is a view in transverse section, enlarged, taken at one edge OfTigure 8.

In practicing the inventions set forth in my Patents 1,034,746 of August 6, 1912, and- -1,029,328 of `June 11, 1912, with the heavier chip paper usually employed in the two ply panel or wallboard, it has been found Figure 1 is a view in perspective, illus lthat the board leavesthe compression or forming roll in the form shown in Figure 6 of Patent 1,029,328, that `is with the edge yof the side margins of the top sheet resting upon and projecting above the inturned edge of the lower covering sheet and the upper face of the top covering sheet is not forced down flush with the upper faces of the inturned laps as shown in Figure 2 of Patent 1,034,746, as is accomplished with the thinner felt paper used in fabricating the four ply plaster board illustrated `in these patents. The result is that with the heavier chip paper, when the topcovering sheet is applied as the board passes under the forming roll, the inturned edge embracing flaps of the bottom sheet are of such stiffness that theyare angularly depressed from the bend at the top corner of the edge, when the edges are scored to form the corners as set forth in my Patents 1,330,413 of February 10, 1920, and 1,383,249 of June 28, 1921, although the uppercorner itself lies in the plane of the upper surface of the top cover sheet there is a. slight depression along each longitudinal edge deepening from the corner of the edge of the board to the bottom of the longitudinal edge of the .top sheet, which depression varies in width in accordance with the slight variations of the posi tion of the top cover sheet caused by the va' riations of the width .of the paper and they slight weaving of the paper in the machine before it is` ap lied tofth'eboard.

On acount of these deje'ssions along each longitudinal edge the topasheet side of the board must be applied next to the studding i to present a smooth exterior surface to the wall or ceiling. It has also been found in the practical manufacture of plaster wallboard in accordance with patents heretofore l mentioned thatv the consistency of the plastic mixture for the core due to mechanical v ject above the adjacent upper corner of the X *edge of the board. The effect of this is that there are hollow spaces left between the covering sheets under the margins adjacent the edges of the top sheet so that when ythe wallboard is applied with-the top cover sheet side against the stud and nailed thereto, the

v'the driving vof the nail through'such hollow spaces causes'the margin of the wallboard lat-that point to be drawn against the stud below the exterior surface of-the adjacent wallboard and at times bends the margin at such edge for a substantial distance causing a depression abutting the uniform edge,

of the adjacent wallboard upon the exterior wall surface.

This invention contemplates various related means for producing plaster wallthroughout, that is the exterior dimension of thickness will be the same throughout each longitudinal bound edge of each Wallboard so that all portions of each side surface will lie in the same respective plane. In such a wallboard either side may form the exterior of the wall and it will not be necessary to .place one particular side against the studding and as each longitudinal edge lboard that will be of uniform thickness when nailed to the studding will uniformly j .the composition core 2 to bind the edges of the'wall board with the margins 3 on each side folded over on top of the core and slightly depressed therein at a slight angle to the top surface, as shown.' The top cover .sheet 4 is laid over the top of the composition core body and over the upper sides of the inturned margins of 'the bottom sheet flaps with sufficient of the composition core material between the margins of the top sheet and flaps to bond Ithem to each other. Soffar the construction is the same as disclosed in my aforesaid patents and the bottom sheet is preferably scored to form the corners of the respective edges as described in the later two of said patents. In order that the edges of the top cover sheet may be brought adjacent or approximately meet theI upper corners of the respective longitudinal edges of the wallboard without projecting thereabove or without depressing the upper surface of the Haps between the corner and the adjacent edge of the top sheet, each margin 5 of each longitudinal edge of thetop sheet is chamfered or beveled on the under side preferably so that each margin will taper from the usual thickness of the cover sheet for a distance approximately the width or less of the inturned. flapof the bottom sheet to the respective edges of the sheet making the margins of this sheet at the edges extremely thin. No matter what the consistency of the plastic core body may be when the board is passedfurrder `the forming roll, at which time the top cover sheet is applied, suiicient of thevplastic mass will be forced between the inturned flaps and margins of the sheet to bond themthroughout to the very edges of the top sheet and allow the top sheet to be applied as a flat surface fromonel upper cornerof the 'longitudinal edge of the wallboard to the other. 'Ilhe usualsmoothing or ironing device throughfwhi'ch the wallboard afterwards passes will not only4 insure the upper corners' ofthe longitudinal edges and entire'upper surface of the top sheet lying in the same plane but will wipe off' any excess of the plastic core mass that may exude beyond the edges of thetop sheet.

' Since the margins of the top sheet taper to an extreme thinness at the edges, lthe top sheet may be cut theexact width of the finished wallboard, or approximately there to, which. will insure. the avoidance of'alongitudinal depression adjacent the edges1 ofthe board on that side. and any variation in the application of thetop sheet causing Vac the sheet to project beyond the edge or edges of the wallboard will not be objec-1 -tionable on account of the thinness and ilexibility of the edges of the margins of the-- top sheet will allow the usual edgestraighteners of the machine to fold such fprojecting portions downward against the. exterior ofsuch edge proper without' noticeably in creasing the dimensions of the wallboard,

likewise, should the variations lin w-idth of the top sheet lay the edge of the tapered margins at a distance from the top corner of the adjacent edge, the taper will cause acorrespondingly less depression of thefbottom sheet flap thereunder as the Aboard passes under the forming roll and that lentire surface of the wallboard from corner to corner of the longitudinal edges will lie in the same plane.

Figure 2 illustrates in enlarged detail the construction above described. Figure 3 illustrates the positions( of two adjacent wallboards as4 nailed to a stud from which it is seen that no matter whichsurface of the vwallboard is placed upon the stud the abutting edges will lie in the same plane also that the entire surfaces of the,

an boardsengagel the-stud throughout. Figure Li'is'another view showingthe manner a'wallboard constructed in accordance with this invention when applied with the top sheet side against the stdwill engage the stud throughout and the nails driven adjacent the edge will not draw the edge board unevenly toward the stud, as in the case of thetop sheet edge projecting kabove the` pla-ne of the top sheet side corners .of the edges of the board.-

Another form lof this invention is illustrated in Figure 5 in which the bottom cover sheet 1 is folded to envelope the longitudinal edges of theplastic composition core 2 with the margins 3 of the edges of this sheetflying upon the top ofthe core, however, the top cover sheet 4 is of suliicient width to be folded about the longitudinal covered edges of the'wallboard to embrace the margins of the bottom cover ysheet and be secured thereto. It is preferable to `score the bottom sheet along the lines where the bends in the folds ofthe margins form the corners of the board before the top sheet is applied and it is also preferable to scoreA the top sheet along the lines where its margins fold over the core edge enveloping portions of the bottom sheet to provide squarecorners. It is preferable to accomplish this scoring of the top cover sheet just before it is `applied to the wallboard so that there .will be an exact 'register with the corners of the bottom sheet when the topA sheet is folded thereover. The margi s 6 of the .top sheet are chamfered or beve ed so that Yedges before subjecting the wallboard with itshcore in plastic condition to the final 'pres sure that determines and maintains the uni- .'form thickness, which pressure lwill also align the folded over'margins of the top sheet in thel same plane with the main portionjof thebottoin sheet. The portions of the top sheet contacting with portions of l the`bottom1sheet may be secured or'bonded thereto throughout the contact or any portion thereof by a, lm of the plastic body lmaterial or by an adhesive, such as silicate or soda, or by a combination of both. As

aforesaid, itis preferable to accomplish the scoring of the top sheet ust before it is aplied, it is also p-referabletov chamfer or vel the margins of the top sheet at the same time or just after .the scoring so that the margins will taper from the outer scored lines to theirl respective edges, and variations in the width of the paper will not affect the finished wallboard because the scorings of the top and bottom sheets are so arranged that` the outer top sheet will em-z brace the 'corners of the bottom sheet fold and the inal pressure in applying the tapering margins of the top sheet on the unv der side of the bottom sheet will cause the angular portions 7 adjacent the innermost scoring of the bottom sheet to be adjusted in accordance with the amount of top` sheet margin applied thereover. If it is desired to maintain the margins 3 of the bottom sheet against the under portions of the en i25 prefera ly at right angles to the e es suficiently to form tongues 8 bent at rlghtangles thereto and which will enter the compositionbody as the margins are'folded down thereover and prevent the folded o ver porvelopin top sheet, the margins may be slit tions becoming depressed into the Aplastic core. In 4this form of this invention the wallboard is reversible, will engage the st ud l throughout its longitudinal edge, and possesses doubly protected longitudinal edges and edge corners.

Another modification is shown in Figures k8 and 9 in which the top cover sheet is cut nal edges and is arranged above the scorings of the bottom sheet that forms the lower corners of the said edges. The margins 9 of the top sheet are chamfered or beveled so that they Will taper from the scorings totheir respective edges and when folded down against the edge covering the portion of the bottom sheet will form rectangular longitudinal edges upon the Wallboard. The scorings upon the bottom sheet are so arranged that the outermost scorings will allow the bend Within the top cover sheet to be made Within the' desired thickness of the Wallboard. The contacting portions of the bottom and top sheets may be bonded or secured by a film lof the plastic body material or by an applied adhesive throughout the entire contact or by any combination of these desired. This form of Wallboard4 ,is reversible and of uniform thickness throughout and its appearance 'or effectiveness is not affected by the variations in Width or Weaving of the top sheet during sheet 4 with these margins chamfered .or

beveled, as 6 in Figure 6the result being the same asif the bottom sheet 1 of' Figure 6 rwas terminated at the scoring for :the bott`om corner bend of .this figure.

What I claim is:

1. A- laster wallboard havingacomposition b y with fibrous cover vsheetsthereon,

one of said cover sheetscnveloping thev edges thereof and engaging 4theother, the margins of one of the sheets formed to provide means' to bring the exterior surfaces thereof into the plane of the corners of the edgesof the board on that side. A

2. A plaster Wallboard having a composition body With fibrous cover sheets thereon, one of Said cover sheets enveloping the edges thereof and engaging the other, and the margins of one cover sheet chamfered to bring the exterior surfaces thereof into the plane of the corners of that side -of the longitudinal edges of the wallboard toengage the opposite side thereof with the other cover sheet secured over the margins of the first sheet, and the margins of the top sheet chamfered to bring the exterior surfaces thereof into the .plane of the corners of that surface of the wallboard'they engage.y Y CLARENCE W. UTZMALN.:

one of said cover sheets passing about the 

